Reduction of Transmitter Intermodulation Product Signals in Air Force Communications Systems

摘要

The report describes the results of a program investigating means of reducing the intermodulation products generated in collocated 100-watt transmitters operating in the 225 to 400 MHz frequency range. The IM reduction technique considered a cascade of four tunable isolators and a standard tunable filter to achieve a net antenna-to-transmitter isolation of 80 dB. The major accomplishment on the program was the development of a tunable, compact, lumped-parameter UHF isolator having a power handling level in excess of 100 watts with a typical forward loss of 0.5 dB, and a 20-dB isolation bandwidth of 4.3 to 7.6 percent. (Author)